OMIM ID:
Coats Plus Syndrome
Alternate Names
Defective Genes
Clinical Characteristics
Ocular Features
Retinal telangiectasia and exudates (Coats disease) occur in association with intracranial cysts, calcifications and extraneurologic manifestations in this condition. Coats disease lesions may also occur in Labrune syndrome (614561) and, of course, in isolation.
Whereas simple Coats disease almost exclusively occurs unilaterally and in males, both sexes and both eyes may have Coats retinal lesions in this syndrome.
Systemic Features
As a result of intracranial calcifications, leukodystrophy and brain cysts, patients have a variety of neurologic signs including spasticity, ataxia, dystonia, cognitive decline, and seizures. Vascular ectasias may also occur throughout the body such as the intestines, stomach, and in the liver increasing the risk of GI bleeding and portal hypertension with anemia and thrombocytopenia. Some individuals have sparse hair, abnormal pigmentation of the skin, and dysplastic nails as well.
Some extraretinal features are also found in patients with dyskeratosis congenita (127550), and in Labrune syndrome (614561).
Genetics
Inheritance
This autosomal recessive pleotropic disorder results from compound heterozygous mutations in the CTC1 gene (17p13.1). Several patients with mutations in STN1 have also been reported.
Most cases of simple Coats disease occur sporadically. No associated locus or mutation has been found.
Pedigree
Autosomal recessive
In order for autosomal recessive disorders to be expressed, offspring generally must inherit two mutations, one from each carrier parent. Carriers with only one mutation, such as the parents, do not have clinical disease. Note that carrier parents can expect that 1 in 4 children (25%) will inherit both mutations and have the disorder, 2 in 4 children (50%) will be carriers like their parents, while 1 in 4 children (25%) inherit neither mutation.
In order for autosomal recessive disorders to be expressed, offspring generally must inherit two mutations, one from each carrier parent. Carriers with only one mutation, such as the parents, do not have clinical disease. Note that carrier parents can expect that 1 in 4 children (25%) will inherit both mutations and have the disorder, 2 in 4 children (50%) will be carriers like their parents, while 1 in 4 children (25%) inherit neither mutation.